1. Field of the Invention
The present invention relates to a silver halide color photographic light-sensitive material, and more specifically, such material having an improved color reproducibility, high sensitivity, high contrast, improved graininess, and improved sharpness.
2. Description of the Related Art
In the field of silver halide color photographic light-sensitive materials, it is conventionally known to utilize the interlayer inhibition effect so as to improve the color reproducibility. In the case of color negative materials, color generation of a red-sensitive layer upon a white exposure can be inhibited more than that upon a red exposure by imparting a development inhibition effect from a green-sensitive layer to a red-sensitive layer. In the case of color negative papers, the gradation is balanced such that gray is reproduced on a color print when exposed by white light. Consequently, the above-mentioned interlayer effect achieves, when subjected to a red exposure, a cyan color having a density higher than the case of gray exposure, and therefore it is possible to reproduce a red color of a higher saturation degree, with inhibited cyan color generation. Similarly, the development inhibition effect from the red-sensitive layer to the green-sensitive layer reproduce a green color having a high saturation degree.
There are several methods for enhancing an interlayer effect. One of them is a technique such as disclosed in JP-A-50-2537, wherein a so-called DIR compound is added to an interlayer effect-imparting layer. The DIR compound is a coupler which releases a development inhibitor when reacting with an oxidized product of a developing agent in a paraphenylenediamine-based color developing solution. Another one is a technique which uses iodide ions released from silver halides during development. More specifically, in this technique, the content of silver iodide of an interlayer effect-imparting layer is increased, and that of a layer which receives such an effect is decreased in advance. Another well-known technique is an automatic masking method in which use is made of a colored coupler.
In particular, regarding the method in which a DIR compound is added to an interlayer effect-imparting layer, it is known that the development inhibitor released from the DIR compound not only achieves the interlayer effect, but also causes a horizontal Eberhard effect so as to enhance the image sharpness since the development inhibitor diffuses also in the direction perpendicular to a light beam made incident.
As disclosed in European Patent 101,621, or JP-A-59-131934, the horizontal Eberhard effect is prominent particularly in the case where the diffusibility of the development inhibitor or a precursor thereof is high, and the effect is advantageous for improvement of, not only color reproducibility, but also sharpness.
With the above-described means, the color reproducibility and sharpness of the color photographic light-sensitive material have been significantly improved; however the amount of the DIR compound contained in the interlayer effect-imparting layer must be inevitably increased so as to enhance the interlayer effect, creating the drawback of significantly inhibiting development of silver halide grains contained in that layer.
More specifically, the silver halide grains contained in an interlayer effect-imparting layer containing a large amount of the DIR compound entail significantly low sensitivity and contrast due to the development inhibitor released from the layer itself during development. If, in order to compensate the lowered performances, the size of the silver halide grains, or the number of the silver halide grains in the interlayer effect-imparting layer is increased, the graininess is degraded, or the sharpness of the under layer is deteriorated.
Thus, despite the demand for further improvement of the color reproducibility, the overall image quality is still not satisfactory, due to the above-described drawbacks. Consequently, there has been demand for means to overcome these drawbacks.
Recently, there have been a progress and improvement in graininess and sharpness achieved by silver halide grains themselves. For example, JP-A-58-113926, JP-A-58-113927, JP-A-58-113928, JP-A-58-113930, and JP-A-58-113934 each disclose a technique of using tabular silver halide grains for the purpose of improving the correlation between sensitivity and graininess, or sharpness.
Further, JP-A-63-220238, and JP-A-1-102547, for example, each disclose a technique for improving a variety of photographic characteristics by introducing dislocations, which are intentionally controlled, to the tabular silver halide grains.
Regarding the tabular silver halide grains, much research has been conducted for improving the graininess and sharpness; however, improvement of the color reproducibility has not been discussed in the research.